Anti-mCD8-mIgG2a InvivoFit™ is a mouse anti-mouse monoclonal antibody (mAb) featuring the variable region of the previously described anti-mCD8 YTS 169.4 clone . Using recombinant technology, the original YTS 169.4 rat IgG2b constant region has been replaced with a murine IgG2a format which mediates potent cytotoxic functions .
CD8 is a transmembrane protein primarily expressed on most thymocytes and highly expressed by the peripheral mature CD8+ T cell population [3, 4]. Two isoforms CD8α (Lyt-2) and CD8β (Lyt-3) are usually co-expressed and form a CD8α/β heterodimer that plays a critical role in CD8+ T cell development and activation. Other immune cells, such as Natural Killer cells and subsets of dendritic cells also express CD8α .
The anti-mCD8 YTS 169.4 mAb is commonly used for in vivo depletion of the CD8+ T cell population to study its role in various immune responses, including in a viral or tumoral context [6-8]. Depending on the nature of the experiment, extended treatment schedules (up to several months) may be required. Upon repeated injection of a xenogeneic mAb, mice produce anti–species antibodies, causing the removal of the administered mAb from circulation, thereby reducing its in vivo efficacy. Moreover, this immunogenicity can lead to fatal hypersensitivity reactions [9-10] which can be reduced by mAb murinization .
Key features of Anti-mCD8-mIgG2a InvivoFit™:
- Derives from the YTS 169.4 clone, rat IgG2b, κ
- Features the mIgG2a isotype (constant region)
- Guaranteed sterile, endotoxin level < 1 EU/mg
- Suitable for parental delivery in mice (azide-free)
- Low aggregation < 5%
- Produced in animal-free facilities and defined media
Anti-mCD8-mIgG2a InvivoFit™ is produced in Chinese hamster ovary (CHO) cells, purified by affinity chromatography with protein A, and provided in an InvivoFit™ grade, a high-quality standard specifically adapted to in vivo studies. The specific binding of this mAb to cell surface mCD8α and its in vivo depleting function have been confirmed (see Figures).
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